From af15520ea6297508f35f42ed452fe188a39dcee4 Mon Sep 17 00:00:00 2001
From: Antonin Delpeuch <antonin@delpeuch.eu>
Date: Sat, 10 May 2025 09:23:59 +0200
Subject: [PATCH] fix: Restrict commutativity in C#

Fixes #224.
---
 .../failing/methods_with_comments/Base.cs     | 20 +++++++++++
 .../ExpectedCurrently.cs                      | 34 +++++++++++++++++++
 .../methods_with_comments/ExpectedIdeally.cs  | 30 ++++++++++++++++
 .../failing/methods_with_comments/Left.cs     | 24 +++++++++++++
 .../failing/methods_with_comments/README      |  3 ++
 .../failing/methods_with_comments/Right.cs    | 26 ++++++++++++++
 src/supported_langs.rs                        | 25 +++++++++++++-
 7 files changed, 161 insertions(+), 1 deletion(-)
 create mode 100644 examples/csharp/failing/methods_with_comments/Base.cs
 create mode 100644 examples/csharp/failing/methods_with_comments/ExpectedCurrently.cs
 create mode 100644 examples/csharp/failing/methods_with_comments/ExpectedIdeally.cs
 create mode 100644 examples/csharp/failing/methods_with_comments/Left.cs
 create mode 100644 examples/csharp/failing/methods_with_comments/README
 create mode 100644 examples/csharp/failing/methods_with_comments/Right.cs

diff --git a/examples/csharp/failing/methods_with_comments/Base.cs b/examples/csharp/failing/methods_with_comments/Base.cs
new file mode 100644
index 0000000..ae2a989
--- /dev/null
+++ b/examples/csharp/failing/methods_with_comments/Base.cs
@@ -0,0 +1,20 @@
+// Copyright header
+
+using System;
+
+namespace MyNamespace;
+
+public partial class MyClass : IMyInterface
+{
+    /// <summary>
+    /// Ctor docs
+    /// </summary>
+    /// <param name="ctorArg">Param docs</param>
+    public MyClass(IThing1 thing1, IThing2 thing2)
+    {
+        _thing1 = thing1;
+        _thing2 = thing2;
+    }
+
+    private record MyPrivateRecord(bool Foo);
+}
diff --git a/examples/csharp/failing/methods_with_comments/ExpectedCurrently.cs b/examples/csharp/failing/methods_with_comments/ExpectedCurrently.cs
new file mode 100644
index 0000000..c389a04
--- /dev/null
+++ b/examples/csharp/failing/methods_with_comments/ExpectedCurrently.cs
@@ -0,0 +1,34 @@
+// Copyright header
+
+using System;
+
+namespace MyNamespace;
+
+public partial class MyClass : IMyInterface
+{
+    /// <summary>
+    /// Ctor docs
+    /// </summary>
+    /// <param name="ctorArg">Param docs</param>
+    public MyClass(IThing1 thing1, IThing2 thing2)
+    {
+        _thing1 = thing1;
+        _thing2 = thing2;
+    }
+
+<<<<<<< LEFT
+    /// <summary>
+    /// Record docs
+    /// </summary>
+    /// <param name="Foo">Bool arg docs</param>
+||||||| BASE
+=======
+    /// <summary>
+    /// Prop docs
+    /// </summary>
+    [MyCustomAttribute]
+    public string? MyProp { get; set; }
+
+>>>>>>> RIGHT
+    private record MyPrivateRecord(bool Foo);
+}
diff --git a/examples/csharp/failing/methods_with_comments/ExpectedIdeally.cs b/examples/csharp/failing/methods_with_comments/ExpectedIdeally.cs
new file mode 100644
index 0000000..1f8ec98
--- /dev/null
+++ b/examples/csharp/failing/methods_with_comments/ExpectedIdeally.cs
@@ -0,0 +1,30 @@
+// Copyright header
+
+using System;
+
+namespace MyNamespace;
+
+public partial class MyClass : IMyInterface
+{
+    /// <summary>
+    /// Ctor docs
+    /// </summary>
+    /// <param name="ctorArg">Param docs</param>
+    public MyClass(IThing1 thing1, IThing2 thing2)
+    {
+        _thing1 = thing1;
+        _thing2 = thing2;
+    }
+
+    /// <summary>
+    /// Prop docs
+    /// </summary>
+    [MyCustomAttribute]
+    public string? MyProp { get; set; }
+
+    /// <summary>
+    /// Record docs
+    /// </summary>
+    /// <param name="Foo">Bool arg docs</param>
+    private record MyPrivateRecord(bool Foo);
+}
diff --git a/examples/csharp/failing/methods_with_comments/Left.cs b/examples/csharp/failing/methods_with_comments/Left.cs
new file mode 100644
index 0000000..2b3702f
--- /dev/null
+++ b/examples/csharp/failing/methods_with_comments/Left.cs
@@ -0,0 +1,24 @@
+// Copyright header
+
+using System;
+
+namespace MyNamespace;
+
+public partial class MyClass : IMyInterface
+{
+    /// <summary>
+    /// Ctor docs
+    /// </summary>
+    /// <param name="ctorArg">Param docs</param>
+    public MyClass(IThing1 thing1, IThing2 thing2)
+    {
+        _thing1 = thing1;
+        _thing2 = thing2;
+    }
+
+    /// <summary>
+    /// Record docs
+    /// </summary>
+    /// <param name="Foo">Bool arg docs</param>
+    private record MyPrivateRecord(bool Foo);
+}
diff --git a/examples/csharp/failing/methods_with_comments/README b/examples/csharp/failing/methods_with_comments/README
new file mode 100644
index 0000000..db3e2cb
--- /dev/null
+++ b/examples/csharp/failing/methods_with_comments/README
@@ -0,0 +1,3 @@
+Commutativity is restricted because comments are involved.
+See https://codeberg.org/mergiraf/mergiraf/issues/224,
+https://codeberg.org/mergiraf/mergiraf/issues/322.
diff --git a/examples/csharp/failing/methods_with_comments/Right.cs b/examples/csharp/failing/methods_with_comments/Right.cs
new file mode 100644
index 0000000..efa2ba8
--- /dev/null
+++ b/examples/csharp/failing/methods_with_comments/Right.cs
@@ -0,0 +1,26 @@
+// Copyright header
+
+using System;
+
+namespace MyNamespace;
+
+public partial class MyClass : IMyInterface
+{
+    /// <summary>
+    /// Ctor docs
+    /// </summary>
+    /// <param name="ctorArg">Param docs</param>
+    public MyClass(IThing1 thing1, IThing2 thing2)
+    {
+        _thing1 = thing1;
+        _thing2 = thing2;
+    }
+
+    /// <summary>
+    /// Prop docs
+    /// </summary>
+    [MyCustomAttribute]
+    public string? MyProp { get; set; }
+
+    private record MyPrivateRecord(bool Foo);
+}
diff --git a/src/supported_langs.rs b/src/supported_langs.rs
index af0ab8c..03d3891 100644
--- a/src/supported_langs.rs
+++ b/src/supported_langs.rs
@@ -473,7 +473,30 @@ pub static SUPPORTED_LANGUAGES: LazyLock<Vec<LangProfile>> = LazyLock::new(|| {
             atomic_nodes: vec![],
             commutative_parents: vec![
                 CommutativeParent::without_delimiters("compilation_unit", "\n"),
-                CommutativeParent::new("declaration_list", "{", "\n", "}"),
+                CommutativeParent::new("declaration_list", "{", "\n", "}").restricted_to_groups(&[
+                    &["using_directive"],
+                    &[
+                        "field_declaration",
+                        "property_declaration",
+                        "event_declaration",
+                        "event_field_declaration",
+                    ],
+                    &[
+                        "class_declaration",
+                        "struct_declaration",
+                        "enum_declaration",
+                        "delegate_declaration",
+                        "method_declaration",
+                        "record_declaration",
+                        "constructor_declaration",
+                        "destructor_declaration",
+                        "indexer_declaration",
+                        "interface_declaration",
+                        "namespace_declaration",
+                        "operator_declaration",
+                        "conversion_operator_declaration",
+                    ],
+                ]),
                 CommutativeParent::new("enum_member_declaration_list", "{", ",\n", "}"),
             ],
             signatures: vec![
-- 
2.47.3